People with diabetes are either deficient in insulin or are unable to make sufficient insulin to overcome underlying insulin resistance or to normalize the glucose metabolism. In order to achieve a better glycemic control or even to regain almost full glycemic control often basal insulin or insulin glargine treatment is used which is based upon a set of rules set for periodic blood glucose measurements in order to obtain information on the progress of the treatment. With regard to this it has to be considered that the blood glucose levels fluctuate throughout the day. A “perfect glucose level” would mean that glucose levels are always in a range of 70 to 130 mg/dl or 3.9 to 7.2 nmol/L and undistinguishable from a person without diabetes.
In order to achieve this or to get as close as possible to such a “perfect glycemic control” blood glucose values are monitored once or several times during the day as relying on their own perception of symptoms of hyperglycemia or hypoglycemia is usually unsatisfactory as mild to moderate hypoglycemia causes no obvious symptoms in nearly all patients. If the blood glucose value is too high, e.g. over 130 mg/dl, insulin or insulin analogues can be administered.
For the insulin therapy long-acting basal insulin or insulin glargine, which are long-acting basal insulin analogues, are used. These insulin or insulin analogues are usually given once daily to help control the blood sugar level of patients with diabetes. The advantage of long-acting basal insulin or insulin glargine is that they have a duration of action of more than 24 hours or even more with a less peaked profile than NPH. Thus, it more closely resembles the basal insulin secretion of the normal pancreatic β-cells.
For good or perfect glycemic control the dose of basal insulin or insulin glargine has to be adjusted for each individual in accordance with a blood glucose level to be achieved. Usually, the dose of insulin or insulin glargine is increased from an initial dose to a final dose over a certain time period until the specific blood glucose value, typically the fasting blood glucose (FBG) value has reached the target range. In practice, such titration can be done by the health care professionals (HCPs). However, the patient may be empowered and trained by the health care professionals to do their own titration. Such a self-titration can be supported by an intervention from a third party support or services or some intermediate combination.
In the every day use basal insulin or insulin glargine are typically under-dosed. Thus, there remains a gap between the initial dosing and an optimal dosing for achieving perfect or almost perfect glycemic control. This has a number of negative effects which better titration could help to eliminate. For example, if patients are not titrated, their blood sugar does not come down and as a result they do not feel better in the short term. Moreover, in the long term their HA1c remains high and their long-term health suffers. Thus, the patients may feel that their treatment is not working and they may lose interest in the therapy or discontinue treatment.
Due to the almost peakless profile basal insulin and insulin glargine are simple to titrate. Meanwhile, there is an array of approaches that physicians use for titration. Some of these approaches are e.g. described in Anthony Barnet, “Dosing of Insulin Glargine in the Treatment of Type 2 Diabetes”, Clinical Therapeutics, vol. 29, no. 6, 2007, pages 987-999; Melanie Davies et al., “Improvement of Glycemic Control in Subjects With Poorly Controlled Type 2 Diabetes”, Diabetes Care, vol. 28, no. 6, June 2005, pages 1282-1288; H. C. Gerstein et al., “A randomized trial of adding insulin glargine vs. avoidance of insulin in people with Type 2 diabetes on either no oral glucose-lowering agents or submaximal doses of metformin and/or sulphonylureas, The Canadian INSIGHT (Implementing New Strategies with Insulin Glargine for Hyperglycaemia Treatment) Study”, Diabetic Medicine, vol. 23, 2006, pages 736-742; H. Yki-Järvinen et al., “Insulin glargine or NPH combined with metformin in type 2 diabetes: he LANMET Study”, Diabetologica; Robert J. Heine et al., “Exenatide versus Insulin Glargine in Patients with Suboptimally Controlled Type 2 Diabetes, A Randomized Trial”, Annals of Internal Medicine, vol. 143, no. 8, October 2005, pages 559-569 and Poul Strange, “Treat-to-Target Insulin Titration Algorithms When Initiating Long or Intermediate Acting Insulin in Type 2 Diabetes”, Journal of Diabetes Science and Technology, vol. 1, issue 4, July 2007, pages 540-548.
Generally, these approaches suggest a specific dose adjustment within a specific time period until the target FBG is achieved. Each of these algorithms comes with specific rules, e.g. that the dose should not be increased if the blood glucose value (BG value) was below 70 mg/dl (low blood sugar) in the last week. Furthermore, health care professionals may set a different FBG target to suit the patient.
Independently of the above referenced publications EP 1 281 351 A2 describes a diabetes management system which enables glycemic control for a subject. The described system includes an insulin delivery unit, a glucose sensor and a control unit. The control unit includes a processor unit that receives glucose value readings from the glucose sensor, executes an algorithm that predicts a glucose value at a predetermined time in the future, compares the predicted glucose value with the predetermined glucose value range, and determines a corrective amount of insulin to be administered when the predicted glucose value lies outside of the predetermined glucose value range. The glucose unit also includes a communication unit that transmits the corrective amount to the delivery unit.